I have been fishing for bout an hour and a half and I cant get any other pokemon other than magikarp or is that all u can get and im being stupid?
You will always get Magikarps when fishing with the Old Rod. Upgrade to a Good Rod in Falonia City.
Is there any special/rare Pokémon you can get with the super rod only?
Do you talk to the same guy to get the super rod?
No you buy at a place called the trainer tower in runko islands far later in the game